1. Field of the Invention
The present invention relates to a device and method for the detection and measurement of hydrazines.
2. Discussion of the Prior Art
Hydrazines such as monomethylhydrazine and unsymmetrical dimethylhydrazine have recently found extensive use as propellants. Unfortunately, the hydrazine vapors are known or suspected of containing carcinogens exhibiting toxic effects in humans at very low, that is, ppm and ppb, levels of exposure. Consequently, it has been necessary to constantly analyze and monitor the environments in which hydrazines are used and handled to insure the safety of people living and/or working in that environment.
Such analysis of hydrazines have heretofore been accomplished by (a) colorimetric analysis, (b) stain tubes and (c) iodine titrations. Instrument techniques have also been applied to the analysis of hydrazines and include derivatization gas chromatography and chemiluminescence. The chromatographic method is non-continuous and requires a chemical vapor treatment prior to analysis while the chemiluminescence method requires prior conversion, by catalytic reaction of the hydrazine vapors, of the hydrazine to NO before detection. However, each of these methods involve a wet chemical step, are non-continuous, and do not analyze the vapors while they are in the gaseous state but require collection of the vapors in the liquid, which is normally an acid solution, or a solid support.
Another difficulty present in hydrazine gas analysis is the unusually high reactivity and/or sorption the gas exhibits with metals and like materials resulting in hydrazine sorption and decomposition reactions. Hence, attempts at analysis of the gas by instrumentation, heretofore, have failed to provide the desired accurate results.
Thus, there is a need for a cost-effective, accurate, reliable and continuous device and method for the analysis of hydrazine vapors which does not have the aforementioned drawbacks of the prior art hydrazine analytical methods.